A petition on the White House website asking President Obama to demand the release of a Marine sergeant in a Mexico prison has garnered more than 100,000 online signatures -- a threshold that typically elicits an administration response.

“The effect of this unjust incarceration on a decorated combat Marine is despairing,” says the petition, which as of Saturday afternoon had 116,051 signatures.

Marine Sgt. Andrew Tahmooressi was arrested March 31 after crossing the Mexican border with three guns in his truck.

Tahmooressi said he accidentally crossed the border and immediately told Mexican authorities that he had three guns in his possession and that he was unable to make a U-turn.

He said he was handcuffed and taken to prison and that his treatment worsened when he tried to escape.